This invention relates to the field of high energy batteries and particularly batteries based on the intercalation compounds of layered transition metal dichalcogenides.
Batteries composed of intercalatable transition metal chalcogenides as the cathode material are known in the art, as exemplified in U.S. Pat. No. 4,009,052 wherein are described alkali metal-based batteries using intercalatable transition metal disulfides such as titanium disulfide as cathode. Such batteries are secondary batteries as distinguished from primary batteries in that they are capable of being charged and discharged over many cycles. Specifically, these batteries are predicated on the use of an intercalated layered dichalogenide like Li.sub.x TiS.sub.2 (in which x varies from 0 to 1) as the cathode-active material and lithium is intercalated or removed to and from the cathode respectively during discharging and charging of the battery. The limiting discharge condition of the battery of the said patent is reached when x approaches 1 as a value.
Thus, there is a need to increase the capacity of the dichalcogenide to intercalate the alkali metal which is transported through the cell to the cathode in order to realize higher capacity of the battery, primarily to obtain greater power from such batteries.
The present invention provides substantially higher capacity than that realized with the batteries of U.S. Pat. No. 4,009,052. For example, the capacity of batteries in accordance with the present invention is up to three times (per mole of the dichalcogenide) that of comparable batteries prepared in accordance with the aforesaid U.S. Pat. No. 4,009,052.